I have been shooting the 284 Win since the mid 80s. Back then the pet load mentioned by the first guy that worked with it in 1963 was Bob Hutton's load: 57 gr of IMR 4350 with a 140 Nosler partition for approximately 3050 fps from a 24" barrel.
I used 57 gr of IMR 4350 with a 140 Sierra Gameking in the beginning to take quite a few coues wt and javelina.
I switched to H4350, which was more temperature stable, and used it with quite a few bullets. When RL-17 showed I switched.
I had my current 284 win rifle altered with bullets seated to fit in a 3.1" SA mag box with OAL of 2.950". Winchester brass, fed 210 match primer, barrel is 23". My reamer is also custom with a short engagement distance to the lands with a 1 1/2 degree throat. I also have to turn the necks to fit the tighter chamber neck.
I used 140, 150 and 160 partitions on elk, 100 gr original X bullet, 140 and 162 bullets for coues wt. over the years.
That 100 gr X bullet using H4350 was close to 3600 but was a poor longer distance bullet. It is out of production now.
Finally settled on the 120 ballistic tip. I could add Steve Timm's comments on this bullet but it is a long one. I could PM it to you if you are interested.
120 gr NBT and RL-17. Please work up carefully to this stopping at 56 or 57.
57 gr is over 3400 fps.
I copied the load data from John Barsness's article on the 284. Unfortunately, he didn't try RL-17:
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